Ios 将UIScrollViewPoint转换为UIImage+；缩放+；旋转

我需要用另一个

UIView

的某个矩形裁剪

UIImage

加载到

uicrollview

中的

UIImage

，该矩形也在

uicrollview

下面是视图层次结构

 --> View
     -->  UIScrollView
        --> viewBase (UIView)
             --> UIImageView -> (Zoomed & rotated )
             --> UIView (Target View)(Movable User can move anywhere in scrollview  to crop rect)

我的图像被旋转和缩放，我需要在

TargetView

我正在绘制

UIImage

，在

context

上旋转，下面是代码

CGFloat angleCroppedImageRetreacted = atan2f(self.imgVPhoto.transform.b, self.imgVPhoto.transform.a);
angleCroppedImageRetreacted = angleCroppedImageRetreacted * (180 / M_PI);

UIView *rotatedViewBox = [[UIView alloc] initWithFrame:CGRectMake(0.0f, 0.0f, self.imgVPhoto.image.size.width, self.imgVPhoto.image.size.height)];
rotatedViewBox.transform = CGAffineTransformMakeRotation(-angleCroppedImageRetreacted);
CGSize rotatedSize = rotatedViewBox.frame.size;

UIGraphicsBeginImageContext(rotatedSize);
CGContextRef bitmap = UIGraphicsGetCurrentContext();
CGContextTranslateCTM(bitmap, rotatedSize.width / 2.0f, rotatedSize.height / 2.0f);
CGContextRotateCTM(bitmap, -angleCroppedImageRetreacted);
CGContextScaleCTM(bitmap, 1.0f, -1.0f);



CGContextDrawImage(bitmap, CGRectMake(-self.imgVPhoto.image.size.width / 2.0f,
                                      -self.imgVPhoto.image.size.height / 2.0f,
                                      self.imgVPhoto.image.size.width,
                                      self.imgVPhoto.image.size.height),
                   self.imgVPhoto.image.CGImage);
UIImage *resultImage = UIGraphicsGetImageFromCurrentImageContext();




UIGraphicsEndImageContext();

而且效果很好。我得到的图像和我在模拟器中看到的一样

对于将目标点视图转换为

UIImage

我使用以下不起作用的代码

 CGPoint imageViewPoint = [self.viewBase convertPoint:self.targetImageview.center toView:self.imgVPhoto];

float percentX = imageViewPoint.x / self.imgVPhoto.frame.size.width;
float percentY = imageViewPoint.y / self.imgVPhoto.frame.size.height;

CGPoint imagePoint = CGPointMake(resultImage.size.width * percentX, resultImage.size.height * percentY);

rect.origin = imagePoint;

//rect.origin.x *= (self.imgVPhoto.image.size.width / self.imgVPhoto.frame.size.width);
//rect.origin.y *= (self.imgVPhoto.image.size.height / self.imgVPhoto.frame.size.height);


imageRef = CGImageCreateWithImageInRect([resultImage CGImage], rect);
img = [UIImage imageWithCGImage:imageRef scale:viewImage.scale orientation:viewImage.imageOrientation];

我认为问题是我们不能在转换应用后使用

Rect

请帮助我裁剪

UIImage

，它在同一层次上从rect缩放和旋转

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如果您需要更多信息，请询问我自己的问题

感谢Matic给了我一个想法

我改变了逻辑

我已经实现了我想要的功能

CGPoint locationInImageView =  [self.viewBase convertPoint:self.targetImageview.center toView:self.view]; // received from touch
locationInImageView =  [self.view convertPoint:locationInImageView toView:self.imgVPhoto];

// I GOT LOCATION IN UIIMAGEVIEW OF TOUCH POINT

UIGraphicsBeginImageContextWithOptions(self.view.frame.size, NO, 0);

[self.imgVPhoto.layer renderInContext:UIGraphicsGetCurrentContext()];

UIImage *img1 = UIGraphicsGetImageFromCurrentImageContext();

UIGraphicsEndImageContext();

// I GOT UIIMAGE FROM  CURRENT CONTEXT 

CGFloat width = self.targetImageview.frame.size.width * self.zoomScale ;
CGFloat height = self.targetImageview.frame.size.height * self.zoomScale ;

 //2 IS SCALE FACTOR 

CGFloat xPos = (locationInImageView.x  * 2)  - width / 2;
CGFloat yPos = (locationInImageView.y * 2) - height / 2;

CGRect rect1 = CGRectMake(xPos, yPos, width, height);

CGImageRef imageRef = CGImageCreateWithImageInRect([img1 CGImage], rect1);


// YAHHH YOU HAVE EXACT IMAGE 
UIImage *img = [UIImage imageWithCGImage:imageRef scale:img1.scale orientation:img1.imageOrientation];

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目标视图和图像视图之间的关系是什么？如果UIImage有方向，我怀疑旋转代码是否有效（试着在运行时拍摄一张肖像照片，并从几个角度确认它是否有效）。如果怀疑从转换视图中提取帧是一个问题，请使用标准方法将当前转换保存为局部变量，将视图转换设置为标识，将帧保存到局部变量集视图转换回保存的值。不幸的是，从滚动视图中提取坐标需要反复试验。然后，将所有内容绘制到图形上下文中可能会再次遇到麻烦，当图像旋转时，所有内容都会升级。但是如果你的视图被正确地绘制，并且你已经清楚地看到了你所需要的，那么也许你应该考虑创建一个视图快照。假设您的图像视图位于另一个视图上，该视图是目标视图的大小和位置。然后随时创建该视图的快照以获取图像。您可能需要将其缩放一点，以将输出图像的大小增加一点…@MaticOblak目标视图是一个小UIView（圆形），它是要裁剪的部分，意味着它是可移动的UIView，由用户设置为裁剪图像中的特定部分view@MaticOblak我做到了！！！！！看到我的答案了吗